Field of the Invention
The present invention relates to a method of identifying the spatial distribution of areas in a sensory area of brain, a program, and a recording medium therefor.
Description of the Related Art
The brains of humans and apes have sensory areas which respectively handle processing of visual, auditory, and other sensory functions. It has been found that some sensory areas can be divided into finer function sites (areas), and attempts are being made to identify the locations and shapes of those areas in order to assess human senses quantitatively. The locations and shapes of areas that form a sensory area of brain are hereinafter referred to as the spatial distribution of areas.
This sensory area model in which a sensory area is divided into areas is called retinotopy in the case of visual sense and tonotopy in the case of auditory sense, and researches about visual sense which is the most important sense are being particularly actively carried out. Areas are identified by presenting a specific sensory stimulus to a subject (human, ape, or the like), and obtaining and analyzing information on brain activity that is observed in response to the stimulus, as disclosed in Wandell, B. A., Dumoulin, S. O., & Brewer, A. A., (2007), “Visual Field Maps in Human Cortex”, Neuron, V. 56, pp. 366-383, and Portcello, T. A., & Velloti, R. B., (Eds.), (2008), “Visual Cortex: New Research”, New York: Nova Science Publishers.
However, existing methods of identifying the spatial distribution of areas have the following problems.
Only a limited few types of sensory stimuli are used in the identification of the spatial distribution of areas, thereby limiting the amount of brain activity information to be analyzed for the identification of the spatial distribution of areas as well. In addition, there are no quantitative criteria at the stage where the obtained brain activity information is analyzed and areas are identified, thus necessitating manual determination by those who have considerable experience.
The existing methods also need to use a stimulus to one sensory area at a time, for example, a visual stimulus alone or an auditory stimulus alone.